Ahead of my interview with tennis mum extraordinaire Judy Murray, I am advised by the slightly jumpy PR not to ask questions about Andy. Hmm – is that the two-time Wimbledon-winning, Olympic gold medallist Sir Andy Murray whom Judy coached as a youngster alongside his Wimbledon mixed-doubles winning champion brother, Jamie? Could be a tricky subject to avoid.

However, we are only a few seconds in when a very jolly Judy drops the ‘A-word’ to tell me: “I took the boys over the road to the local tennis club because they had so much energy and I just had to get them out of the house. Luckily both Jamie and Andy loved the sport immediately and it went from there.”

Phew. Glad we got that out of the way. Judy first entered the nation’s consciousness as the stony-faced, mum-of-steel who sat rigid in the players’ box at Grand Slam tennis competitions, breaking the pose only to execute an aggressive fist pump as her sons rose through the tennis ranks.

“Being a parent of a child who does an individual sport can be tricky,” explains the 58-year-old. “For the early years you are coach, taxi driver, chef, psychologist – whatever they need really. There is no team bus or collective team talk, it’s just you and them and it’s not easy – and it’s very expensive.”

Judy’s experience as a mother of champions led her to be approached by publisher Penguin to share her knowledge with other parents. The book, Knowing the Score: My Family and our Tennis Story, has been a great success, and has now led to a live ‘audience with’ style of show that arrives at the New Wimbledon Theatre this month to coincide with the town’s world famous championships.

“As part of the book publicity, I did a lot of signings and events and I was really surprised by how much I enjoyed them. So when I was approached about the show, I thought ‘why not?’”

Judy has dedicated her life to the sport of tennis from young player to volunteer with her local club back in Dunblane, to coaching the Scottish Fed Cup team. And while she was happy in her sport, her life and reputation were both given something of an about-face when she appeared on Strictly Come Dancing.

“When the offer came, I asked the boys what they thought and they gave their typical responses. Jamie said, ‘Go on, you will love it’, while Andy said, ‘Oh my God no, you will be rubbish,’. In the end they were both right. I absolutely loved every minute and I was absolutely awful.

“It was the first thing I had done for myself, ever. And it was amazing. I have made some wonderful friends – especially Anton (du Beke) my poor partner. He was so supportive but I was prepared for the harsh comments from Bruno and Craig and I just thought each week, ‘bring it on’.”

The public warmed instantly to Judy, recognising her efforts and keeping her in for an impressive eight weeks. “It was lovely to know people were behind me. It raised my profile and that has helped with my work within tennis.”

As well as writing, supporting her sons and being a grandma to Andy’s two young daughters with wife Kim, Judy works tirelessly to promote the sport she loves in areas where it may not be widely represented.

“Andy’s success has raised the profile of the sport,” she says. “But we have to move faster. Sadly lots of the public courts have gone from parks to make way for cafes or skate parks, which means a lot of the courts remain in private schools and clubs which add to the middle class image. Sport has to be fun, affordable and accessible and to get people playing is what I have always done and what I want to continue to do.”

To find out more, join Judy for In Conversation with Judy Murray at New Wimbledon Theatre, Jul 1. Visit: atgtickets.com